LOCAL FIBRINOLYSIS AND ASPIRATION OF INTRACEREBRAL HEMATOMAS IN RATS - AN EXPERIMENTAL-STUDY USING MR MONITORING

Serial magnetic resonance (MRI imaging has not yet been validated in t he therapy of experimental intracerebral hematomas in a rat model. It is possible to test the effect of local fibrinolysis and aspiration on the clot volume using serial magnetic resonance imaging and different MR-sequences. Experiments were carried out in 22 male Sprague-Dawley rats. Intracerebral hematoma was produced by injection of fresh autolo gous blood into the caudate nucleus using a double injection technique . Thirty minutes later 10 rats were treated by injecting 12 mu l of re combinant tissue plasminogen activator. MR-imaging was performed immed iately after generation of the hematoma and after clot lysis. The clot volume measured in the magnetic resonance images was compared with th at obtained in stained histological serial sections at the end of the experiment. Serial MR scanning demonstrated a significant reduction (p < 0.01) of hematoma volume after fibrinolysis followed by aspiration of the blood clot. The best correlation between MR-and histological vo lumetry was found on RF-spoiled FLASH 2D-images. This study documents the efficacy of MRI in detecting and delineating the size of acute int racerebral hematomas and its time course. Local fibrinolysis and aspir ation can be simulated in an experimental rat model.